1. Field of Invention
This invention relates to a semiconductor package. More particularly, the present invention is related to a thermal enhance semiconductor package with a universal heat spreader having through holes and heat transmission pins therein.
2. Related Art
Integrated circuit (chip) packaging technology is becoming a limiting factor for the development in packaged integrated circuits of higher performance. Semiconductor package designers are struggling to keep pace with the increase in pin count, size limitations, low profile, and other evolving requirements for packaging and mounting integrated circuits.
Originally, in the conventional semiconductor package, the active surface of the chip faces down and is attached to the carrier via metal bumps or solder bumps so as to electrically connect the chip and the carrier. Due to short electrical connection paths between the chip and the carrier, small package size, easy control for high frequency noise and lower signal delays, the flip chip technology is broadly utilized in the recent days.
As we know, the conventional flip chip package is characterized in that the back surface of the chip is directly exposed to the outside without disposing any further heat spreader on the back surface of the chip. Accordingly, it is easy to cause the chip to be damaged due to lack of protective layer on the chip. Furthermore the heat arisen out of the chip is accumulated inside and the heat can't be transmitted to the outside. Thus the life of the chip will be shortened.
Additionally, in order to upgrade the efficiency of the heat dissipation, flip chip package can be in the form of another types. As shown in FIG. 1, a high performance flip chip ball grid array package (HF-BGA) is disclosed. Such semiconductor package 1 mainly comprises a carrier 11, a semiconductor chip 12, a plurality of solder bumps 13, an underfill 14 and a heat spreader 15. The semiconductor chip 12 is flipped and faced down, and electrically connected to the carrier 11 via the solder bumps 13. And the underfill 14 is filled and disposed between the semiconductor chip 12 and the carrier 13 so as to lower the thermal stress caused by the change of the temperature.
Furthermore, the solder balls 16 are disposed on the surface opposed to the surface for the chip being attached thereon and electrically connected to other external devices. And the heat spreader 15 is attached to the semiconductor chip 12 by the heat transmission adhesive 17 so that the heat arisen out of the semiconductor chip 12 can be transmitted to the outside through the heat transmission adhesive 17 and the heat spreader 15. Besides, a stiffener ring 18 is provided on the carrier 11 so as to support the heat spreader 15 and to prevent the heat spreader 15 being tilted.
Next, referring to FIG. 2, a similar semiconductor package is disclosed. When the size of the semiconductor chip 22 is large enough that the stiffener ring can be eliminated. It should be noted that the reference numeral of each element in FIG. 2 corresponds to the reference numeral of each element in FIG. 1.
As shown in FIG. 1, the heat arisen out of the semiconductor chip 12 is transmitted to the outside not only through the back surface of the semiconductor chip 12 and the heat transmission adhesive 17 but also through the stiffener ring 18, the carrier 11 and the solder balls 16. And, as shown in FIG. 2, the heat arisen out of the semiconductor chip 22 is transmitted to the outside not only through the back surface of the semiconductor chip 22 and the heat transmission adhesive 27 but also through the carrier 21 and the solder balls 26. Furthermore the heat can also be transmitted to the outside via the air encompassing the semiconductor chip 12 and 22. However, there is not enough space for the air convection between the semiconductor chip and the carrier 11 so that the heat transmission by air convection is not good. Thus the efficiency of heat dissipation for a semiconductor package is lowered.
Therefore, providing another thermal enhance package to solve the mentioned-above disadvantages is the most important task in this invention.